Five easy lies

A trend

“Holy schmoly! What are we going to do about this darn graph?”

Don’t panic! Just follow these simple instructions…

Choose your cutoffs

Just look at the end

“The trend shows no increase for the last [n] days/months/years.”

Don’t mention the previous [20 n] data points.

Talk about the trend of the trend

“Sure the graph is going up for now, but the rate of increase is going down.”

If this fails, talk about the rate of increase of the rate of increase. Keep on differentiating until you find a curve that matches your needs. If all else fails, try logarithms.

Count the phases

“There are just as many downward phases as upward phases.”

There will always be as many up phases as down phases (plus or minus one). Make sure you distract listeners from the magnitude of the phases.

Choose an outlier

“If there really is an upward trend, how can we explain the result from Convenienceville?”

In any large body of noisy data there will be subsets that do not fit the overall trend. Be sure to remove all error bars from your graph as these will give the game away.

Sow confusion

“There is so much doubt about the trend that we can’t say anything until we have more evidence.”

Evidence is your friend. More evidence means more cutoffs to choose from, more trends to analyse, more phases to count, more outliers to discover, and more confusion to sow. Be careful to disguise the fact that you and not the data are the source of the confusion.

17 People have left comments on this post



» Reed Braden said: { Aug 12, 2009 - 09:08:11 }

Brilliant! I see this kind of garbage all the time. Thanks for laying it all out so amusingly!

» Phil Stevens said: { Aug 12, 2009 - 12:08:13 }

1) There is a trend in the upward direction.

2) Your third graph seems vaguely reminiscent of Elliot Wave market analysis. Look them up.

3) convienceville, KY is an outlier, is not typical of the data, and has been removed from this analysis.

» Graham Clements said: { Aug 12, 2009 - 04:08:39 }

So you’ve been watching the finance guy on the ABC news too.

» cody said: { Aug 13, 2009 - 01:08:58 }

I don’t know whats so funny, times have been rough here in convenienceville.

» Jen said: { Aug 13, 2009 - 03:08:30 }

How about:
-Eliminate some of the data points, so that the lower dots are gone
-Along with choosing your cutoffs, start your y-axis at a non-zero number. I have seen this done in graphs in magazine ads–very misleading.

» Chris Lawson said: { Aug 13, 2009 - 07:08:58 }

Reed: thank you.

Phil: I checked out Elliot Waves and the similarities are as you say pretty amusing. I’m glad you pointed out removing outliers — I might deal with that in a later post.

Graham: I haven’t been watching any finance guys on TV, but I do read the business magazines for a chuckle whenever I’m in a waiting room.

Cody: I’m sorry about the troubles in Convenienceville. If only y’all would vote for [candidate].

Jen: I decided to limit myself to five lies for this post. And who said the y-axis started at zero? :~)

» Athena Andreadis said: { Aug 17, 2009 - 07:08:31 }

You forgot the most obvious ploy: turn it 90 degrees CW or CCW.

» dav said: { Aug 18, 2009 - 01:08:12 }

You can also stretch out the x axis and flatten that graph.

» Leopold said: { Aug 19, 2009 - 06:08:52 }

I’m a professional investor. I love this presentation. It is amazing the nonsense people continually come up with. The best part of it is: Most of them believe their own nonsense.

The problem is people are programmed to want to recognize patterns. We are very good at making out straight lines. The problem with finance is: there are no straight lines. There are no curved lines. And so our primitive biological senses that are good for telling us the quickest route to some food are terrible at figuring out a subject like finance.

People keep getting it wrong over and over ad nauseum, and they don’t get it. Selective memory: We remember our wins, and forget our losses. So we keep thinking we are doing a good job predicting when we just aren’t qualified to.

I keep track of every profit and every loss in a spreadsheet. It is humbling. But that’s just what I am these days: humble.

» Melody said: { Aug 28, 2009 - 04:08:15 }

Ha! Brings me back to my statistics class I took about four years ago. The textbook showed an example of a graph distorting the info, by using a 3D orange, with the majority side mostly obscured, so that it looked like more people thought organic foods were safer or were unsure, even though about 2/3 disagreed. I also remember graphs where the y axis would start at 40 or 200 or something. Er, yeah.

» Dave said: { Nov 4, 2009 - 08:11:46 }

You see this a lot on Fox News.

» Chris Lawson said: { Nov 4, 2009 - 06:11:00 }

I have only watched Fox News on a handful of occasions. It was a handful too much.

» Alex said: { Sep 2, 2010 - 06:09:56 }

It’s cold in Minnesota and temperatures have changed plenty of times before, so CLEARLY there’s no global warming!

Good lesson, man.

{ Jan 1, 2010 - 01:01:45 } Returning to Duty « Impact Analysis

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